In the prior art, there is a semiconductor device in which a semiconductor chip is flip-chip connected on a wiring substrate. In such semiconductor device, in order to attain the further higher density of the mounting, a technique is developed in which a first semiconductor chip is flip-chip connected on the wiring substrate, then a second semiconductor chip is flip-chip connected on the first semiconductor chip and they are stacked.
A related art is disclosed in Japanese Laid-open Patent Publication No. 2013-55313.